title: (E)-6,8-Di-chloro-3-{[(naphthalen-1-ylmeth-yl)iminiumyl]meth-yl}-2H-chromen-4-olate.
abstract: In the title compound, C21H15Cl2NO2, the H atom of the -OH group is transferred to the N atom of the imine, forming a zwitterion. Thus, there is formation of a six-membered ring via an intra-molecular O⋯H-N, rather than O-H⋯N, hydrogen bond in the mol-ecule. The dihedral angle between the naphthalene ring system and the benzene ring of the 2H-chromen system is 87.41 (4)°. In the crystal, the mol-ecules are packed through N-H⋯O, π-π [centroid-centroid distances = 3.744 (3) and 3.780 (3) Å], C-Cl⋯π [Cl⋯centroid = 3.261 (3) Å], C-H⋯π and C-H⋯O inter-actions.
authors.affiliation: School of Pharmaceutical Sciences, University of Shizuoka, 52-1 Yada, Suruga-ku, Shizuoka 422-8526, Japan.
authors.forename: Yoshinobu
authors.initials: Y
authors.lastname: Ishikawa
authors.forename: Yuya
authors.initials: Y
authors.lastname: Motohashi